Immanuel Kant, (born
April 22, 1724, Königsberg, Prussia [now Kaliningrad, Russia]—died
February 12, 1804, Königsberg), German philosopher whose
comprehensive and systematic work in epistemology (the theory of knowledge), ethics, and aesthetics greatly influenced all subsequent philosophy, especially the various schools of Kantianism and idealism.

Background and early years

Kant lived in the remote province where he was born for his entire
life. His father, a saddler, was, according to Kant, a descendant of a
Scottish immigrant, although
scholars have found no basis for this claim; his mother, an uneducated
German woman, was remarkable for her character and natural intelligence.
Both parents were devoted followers of the Pietist branch of the Lutheran church, which taught that religion belongs to the inner life expressed in simplicity and obedience to moral law.
The influence of their pastor made it possible for Kant—the fourth of
nine children but the eldest surviving child—to obtain an education.

At the age of eight Kant entered the Pietist school that his pastor directed. This was a Latin
school, and it was presumably during the eight and a half years he was
there that Kant acquired his lifelong love for the Latin classics,
especially for the naturalistic poet Lucretius. In 1740 he enrolled in the University of Königsberg as a theological student. But, although he attended courses in theology and even preached on a few occasions, he was principally attracted to mathematics and physics. Aided by a young professor who had studied Christian Wolff, a systematizer of rationalist philosophy, and who was also an enthusiast for the science of Sir Isaac Newton, Kant began reading the work of the English physicist and, in 1744, started his first book, Gedanken von der wahren Schätzung der lebendigen Kräfte (1746; Thoughts on the True Estimation of Living Forces), dealing with a problem concerning kinetic
forces. Though by that time he had decided to pursue an academic
career, the death of his father in 1746 and his failure to obtain the
post of undertutor in one of the schools attached to the university
compelled him to withdraw and seek a means of supporting himself.

Otto Allen Bird

Tutor and Privatdozent

He found employment as<script
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a family tutor and, during the nine years that he gave to it, worked
for three different families. With them he was introduced to the
influential society of the city, acquired social grace, and made his
farthest travels from his native city—some 60 miles (96 km) away to the
town of Arnsdorf. In 1755, aided by the kindness of a friend, he was
able to complete his degree at the university and take up the position
of Privatdozent, or lecturer.

Three dissertations that he
presented on obtaining this post indicate the interest and direction of
his thought at this time. In one, Meditationum Quarundam de Igne Succincta Delineation
(1755; “A Brief Outline of Some Meditations on Fire”), he argued that
bodies operate on one another through the medium of a uniformly diffused
elastic and subtle matter that is the underlying substance of both heat
and light. His first teaching was in mathematics
and physics, and he was never to lose his interest in scientific
developments. That it was more than an amateur interest is shown by his
publication within the next few years of several scientific works
dealing with the different human races, the nature of winds, the causes
of earthquakes, and the general theory of the heavens. In the latter
work, Allgemeine Naturgeschichte und Theorie des Himmels (1755; Universal Natural History and Theory of the Heavens),
Kant proposed a nebular theory of the formation of the solar system,
according to which the Sun and the planets condensed from a single
gaseous cloud. Independently advanced by Laplace in 1796, it was
subsequently known as the Kant-Laplace hypothesis.

At this period
Newtonian physics was important to Kant as much for its philosophical
implications as for its scientific content. A second dissertation, the Metaphysicae cum Geometria Iunctae Usus in Philosophia Naturali, Cuius Specimen I. Continet Monadologiam Physicam (1756; The Employment in Natural Philosophy of Metaphysics Combined with Geometry, of Which Sample I Contains the Physical Monadology)—also known as the Monodologia Physica—contrasted
the Newtonian methods of thinking with those employed in the philosophy
then prevailing in German universities. This was the philosophy of Gottfried Wilhelm Leibniz, a universal scholar, as systematized and popularized by Wolff and by Alexander Gottlieb Baumgarten, author of a widely used text, the Metaphysica
(1739). Leibniz’s works as they are now known were not fully available
to these writers, and the Leibnizian philosophy that they presented was
extravagantly rationalistic, abstract,<script
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and cut-and-dried. It nevertheless remained a powerful force, and the
main efforts of independent thinkers in Germany at the time were devoted
to examining Leibniz’s ideas.

In a third dissertation, Principiorum Primorum Cognitionis Metaphysicae Nova Dilucidato (1755; “New Elucidation of the First Principles of Metaphysical Cognition”), Kant analyzed especially the principle of sufficient reason, which in Wolff’s formulation asserts that for everything there is a sufficient reason
why it should be rather than not be. Although critical, Kant was
cautious and still a long way from challenging the assumptions of
Leibnizian metaphysics.

During the 15 years that he spent as a Privatdozent,
Kant’s renown as a teacher and writer steadily increased. Soon he was
lecturing on many subjects other than physics and mathematics—including logic, metaphysics, and moral philosophy.
He even lectured on fireworks and fortifications and every summer for
30 years taught a popular course on physical geography. He enjoyed great
success as a lecturer; his lecturing style, which differed markedly
from that of his books, was humorous and vivid, enlivened by many
examples from his reading in English and French literature and in travel and geography, science and philosophy.

Although
he twice failed to obtain a professorship at Königsberg, he refused to
accept offers that would have taken him elsewhere—including the
professorship of poetry
at Berlin that would have brought greater prestige. He preferred the
peace and quiet of his native city in which to develop and mature his
own philosophy.

During the 1760s Kant became increasingly critical of
Leibnizianism. According to one of his students, Kant was then attacking
Leibniz, Wolff, and Baumgarten, was a declared follower of Newton, and
expressed great admiration for the moral philosophy of the Romanticist
philosopher Jean-Jacques Rousseau.

His principal work of this period was Untersuchung über die Deutlichkeit der Grundsätze der natürlichen Theologie und der Moral
(1764; “An Inquiry into the Distinctness of the Fundamental Principles
of Natural Theology and Morals”). In this work he attacked the claim of
Leibnizian philosophy that philosophy should model itself on mathematics
and aim at constructing a chain of demonstrated truths based on
self-evident premises. Kant argued that mathematics proceeds from
definitions that are arbitrary, by means of operations that are clearly
and sharply defined, upon concepts that can be exhibited in concrete
form. In contrast with this method, he argued that philosophy must begin
with concepts that are already given, “though confusedly or
insufficiently determined,” so that<script
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philosophers cannot begin with definitions without thereby shutting
themselves up within a circle of words. Philosophy cannot, like
mathematics, proceed synthetically;
it must analyze and clarify. The importance of the moral order, which
he had learned from Rousseau, reinforced the conviction received from
his study of Newton that a synthetic philosophy is empty and false.

Besides attacking the methods of the Leibnizians, he also began criticizing their leading ideas. In an essay, Versuch, den Begriff der negativen Grössen in die Weltweisheit einzuführen (1763; An Attempt to Introduce the Conception of Negative Quantities into Philosophy), he argued that physical opposition as encountered in things cannot be reduced to logical contradiction, in which the same predicate is both affirmed and denied, and, hence, that it is pointless to reduce causality to the logical relation of antecedent and consequent. In an essay of the same year, Der einzig mögliche Beweisgrund zu einer Demonstration des Daseyns Gottes (Enquiry into the Proofs for the Existence of God), he sharply criticized the Leibnizian concept of Being by charging that the so-called ontological argument, which would prove the existence of God by logic
alone, is fallacious because it confuses existential with attributive
statements: existence, he declared, is not a predicate of attribution.
Moreover, with regard to the nature of space, Kant sided with Newton in his confrontation with Leibniz. Leibniz’s view, that space is “an order of co-existences” and that spatial differences can be stated in conceptual terms, he concluded to be untenable.

Some indication of a possible alternative of Kant’s own to the Leibnizian position can be gathered from his curious Träume eines Geistersehers erläutert durch Träume der Metaphysik (1766; Dreams of a Spirit-Seer, Illustrated by Dreams of Metaphysics). This work is an examination of the whole notion of a world of spirits, in the context of an inquiry into the spiritualist claims of Emanuel Swedenborg,
a scientist and biblical scholar. Kant’s position at first seems to
have been completely skeptical, and the influence of the Scottish
skeptical philosopher David Hume
is more apparent here than in any previous work; it was Hume, he later
claimed, who first awoke him from his “dogmatic slumber.” Yet Kant was
not so much arguing that the notion of a world of spirits is illusory as
insisting that humans have no insight into the nature of such a world, a
conclusion that has devastating implications for metaphysics as the
Leibnizians conceived<script
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it. Metaphysicians can dream as well as spiritualists, but this is not
to say that their dreams are necessarily empty; there are already hints
that moral experience can give content to the ideal of an “intelligible
world.” Rousseau thus here acted upon Kant as a counterinfluence to
Hume.

(1724-1804). The philosopher Immanuel Kant set forth a chain of
explosive ideas that humanity has continued to ponder since his time. He
created a link between the idealists-those who thought that all reality
was in the mind-and the materialists-those who thought that the only
reality lay in the things of the material world. Kant’s ideas on the
relationship of mind and matter provide the key to understanding the
writings of many 20th-century philosophers.

The topic Immanuel Kant is discussed at the following external Web sites.

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